Biodegradable litter box



FIG. 1 is a front perspective view of a biodegradable litter box;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a rear elevation view thereof;

FIG. 7 is a left side elevation view thereof;

FIG. 8 is a bottom plan view thereof;

FIG. 9 is a rear perspective view thereof showing the cover in analternate position;

FIG. 10 is another rear perspective view thereof showing the retractablecover in an alternate position; and,

FIG. 11 is another rear perspective view thereof showing the cover in aclosed position.

The broken lines are for illustration only and form no part of theclaimed design.

CLAIM The ornamental design for a biodegradable litter box, as shown anddescribed above.